Polyurethanes are among the most versatile polymers because of the wide range of monomers, particularly diols or polyols, that can be utilized in their synthesis. This Review focuses on the most recent advances made in the production of polyurethane materials from vegetable oils. Over the past several years, increasing attention has been given to the use of vegetable oils as feedstocks for polymeric materials, because they tend to be very inexpensive and available in large quantities. Using various procedures, a very broad range of polyols or diols and in some cases, poly- or diisocyanates, can be obtained from vegetable oils. The wide range of vegetable oil-based monomers leads to a wide variety of polyurethane materials, from flexible foams to ductile and rigid plastics. The thermal and mechanical properties of these vegetable oil-based polyurethanes are often comparable to or even better than those prepared from petroleum and are suitable for applications in various industries.

Novel biocomposites have been prepared by the free radical polymerization of a tung oil-based resin using spent germ, the coproduct of wet mill ethanol production, as a filler. The effect of filler particle size, amount of filler, amount of crosslinker, and molding pressure on the resulting composites has been investigated. When compared to the pure resin, an increase in storage modulus is observed when filler is added to the matrix. The thermal stabilities of the resulting composites lie between the stabilities of the resin and the spent germ. Decreasing the particle size results in an increase in both the storage modulus and the mechanical properties of the composites. As the amount of crosslinker, divinylbenzene, increases, an improvement in the thermal stabilities and mechanical properties is observed. The composites prepared are mainly composed of renewable resources, possess good thermal and mechanical properties, and have potential applications in the construction and automotive industries.

No abstract

No abstract

Soybean‐oil‐based cationic polyurethane coatings with antibacterial properties have been prepared with a range of different molar ratios of hydroxyl groups from an amine diol. A second series of polyurethane coatings were prepared from soy polyols with different hydroxyl numbers. All of the cationic PU dispersions and films exhibit inhibitory activity against three foodborne pathogens: Salmonella enterica ssp. enterica ser. Typhimurium, Listeria monocytogenes, and Staphylococcus aureus. It is generally observed that increases in the ratio of ammonium cations improve the antibacterial performance. Reduction of the crosslink density by decreasing the hydroxyl number of the soy polyol also results in slightly improved antibacterial properties. Higher glass transition temperatures and improved mechanical properties are observed with corresponding increases in the molar ratios of the amine diol and the diisocyanate. These results show that the mechanical properties of these coatings can be tuned, while maintaining good antibacterial activity.